This invention relates generally to bushing assemblies and more particularly to a spacer bushing assembly for use in automotive vehicle seat assemblies.
Automotive vehicle seat hinges typically have a problem with excessive movement in a lateral direction, i.e., from side to side, as the seat back is rotated forward and backward. In conventional constructions, the pivot side of the back frame assembly in the vehicle seat is free to slide laterally over the sleeve bushing and/or hinge pin provided to connect the back to the seat. This lateral freedom often results in an undesirable squeaking noise when the back frame slides on the hinge pin.
The present invention eliminates this undesirable noise by capturing the back frame at the hinge allowing minimal lateral motion. The bushing in turn is held together by interlocking shoulders on the bushing itself in addition to being laterally held in place by the pivot pin inserted through the bushing.
The bushing assembly according to the present invention is a plastic assembly designed for use in the vehicle seat assembly having a generally horizontal seat frame and a generally upright back frame, and a pair of hinges connecting the back frame to the seat frame. Each hinge has a hinge pin aligned on a central axis. The hinge pin is secured to the seat frame and the back frame is pivotally supported on the hinge pin to allow pivotable movement of the back frame about the axis of the pin. The bushing assembly according to the present invention is mounted on the hinge pin so as to pivotally support the back frame member and maintain it in a predetermined position spaced from the seat frame member.
The bushing assembly includes a pair of interlocking plastic sleeves each having an annular portion forming a bore therethrough centered on the axis and a pair of opposing tang portions extending axially along the bore from the annular portion. At the distal end of each of the tang portions, a retaining shoulder projects outward radially from the tang. This projection is designed to interlock with a recessed ledge in the annular portion of the other sleeve when the pair of sleeves are inserted one within the other. These projections snap fit onto the corresponding ledges and form a smooth bore through the center of the interlocked sleeves for passage of the hinge pin.
Each of the back frame members has an elongated end having a hinge bore therethrough for passage of the hinge pin. The bushing assembly is assembled by passing the tang portions through the hinge bore and snapping the assembly together sandwiching the back frame member between the annular portions. The opposing faces of the annular portions of the interlocked sleeves provide shoulders on either side of the upright back frame member. The annular portions provide a spacer between the assembled seat and back frame members to limit lateral movement of the frame member at the hinge. Limiting this side to side axial movement of the frame members when the frame members are connected by the hinge in accordance with the present invention precludes undesirable noise generation.
One preferred embodiment of the present invention includes identical sleeves which sandwich the upright back frame member in a centered position between the ends of the sleeves and space the back frame member from the seat frame member. In an alternative embodiment of the present invention, the sleeves have tangs and annular portions of differing lengths proportionately so as to offset the frame members on the bushing assembly.
Another alternative embodiment of the present invention includes a plurality of the plastic sleeves stacked together with the tang portions pointing in the same direction so that the tang portions of one sleeve engage the annular portion of the adjacent sleeve so as to form a series of sleeves snapped together to form a flexible bushing assembly. The length of the assembly can be varied by snapping a number of the sleeves together.
Other features, benefits and advantages of the present invention will become apparent to those skilled in the art to which this invention pertains from the following detailed description and appended claims when taken in conjunction with the accompanying drawings.